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HOW TO PROVE THE DISCRETE RELIABILITY FOR NONCONFORMING FINITE ELEMENT METHODS

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Journal of Computational Mathematics 2020年第1期38卷 142-175页

作者： Carsten Carstensen Sophie Puttkammer Department of Mathematics Humboldt-Universitat zu BerlinUnter den Linden 610099 BerlinGermany

Optimal convergence rates of adaptive finite element methods are well understood in terms of the axioms of *** key ingredient is the discrete reliability of a residualbased a posteriori error estimator,which controls the error of two discrete finite element solutions based on two nested *** the error analysis of nonconforming finite element methods,like the Crouzeix-Raviart or Morley finite element schemes,the difference of the piecewise derivatives of discontinuous approximations to the distributional gradients of global Sobolev functions plays a dominant role and is the object of this *** nonconforming interpolation operator,which comes natural with the definition of the aforementioned nonconforming finite element in the sense of Ciarlet,allows for stability and approximation properties that enable direct proofs of the reliability for the residual that monitors the equilibrium *** novel approach of this paper is the suggestion of a right-inverse of this interpolation operator in conforming piecewise polynomials to design a nonconforming approximation of a given coarse-grid approximation on a refined *** results of this paper allow for simple proofs of the discrete reliability in any space dimension and multiply connected domains on general shape-regular triangulations beyond newest-vertex bisection of *** attention is on optimal constants in some standard discrete estimates listed in the appendices.

关键词： Discrete reliability Nonconforming finite element method Conforming companion Morley Crouzeix-Raviart Explicit constants Axioms of adaptivity

Electrical properties and microstructure formation of V/Al-based n-contacts on high Al mole fraction n-AlGaN layers

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Photonics Research 2020年第8期8卷 1381-1387页

作者： LUCA SULMONI FRANK MEHNKE ANNA MOGILATENKO MARTIN GUTTMANN TIM WERNICKE MICHAEL KNEISSL Institut für Festkorperphysik Technische Universitat Berlin10623 BerlinGermany Ferdinand-Braun-Institut Leibniz-Institut fur Höchstfrequenztechnik12489 BerlinGermany Institut für Physik Humboldt Universität zu Berlin12489 BerlinGermany

The electrical and structural properties of V/Al-based n-contacts on n‐AlxGa1−xN with an Al mole fraction x ranging from x=0.75 to x=0.95 are *** n-contacts are obtained up to x=0.75 with a contact resistivity of 5.7×10^−4Ω·cm^2 whereas for higher Al mole fraction the IV characteristics are *** electron microscopy reveals a thin crystalline AlN layer formed at the metal/semiconductor interface upon thermal *** analysis confirmed an Al enrichment at the *** interfacial nitride-based layer in n-contacts on n‐Al0.9Ga0.1N is partly amorphous and heavily contaminated by *** role and resulting limitations of Al in the metal stack for n-contacts on n-AlGaN with very high Al mole fraction are ***,ultraviolet C(UVC)LEDs grown on n‐Al0.87Ga0.13N and emitting at 232 nm are fabricated with an operating voltage of 7.3 V and an emission power of 120μW at 20 mA in cw operation.

关键词： AlGaN fraction properties

Complete Convergence and Complete Moment Convergence for Maximal Weighted Sums of Extended Negatively Dependent Random Variables

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Acta Mathematica Sinica,English Series 2018年第10期34卷 1501-1516页

作者： Ji Gao YAN School of Mathematical Sciences Soochow University C.A.S.E.-Center for Applied Statistics and Economics Humboldt-Universitt zu Berlin

In this paper, the complete convergence and complete moment convergence for maximal weighted sums of extended negatively dependent random variables are investigated. Some sufficient conditions for the convergence are provided. In addition, the Marcinkiewicz Zygmund type strong law of large numbers for weighted sums of extended negatively dependent random variables is obtained. The results obtained in the article extend the corresponding ones for independent random variables and some dependent random variables.

关键词： Extended negatively dependent complete convergence complete moment convergence maximal weighted sums strong law of large numbers

Fourth-Order Splitting Methods for Time-Dependant Differential Equations

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Numerical Mathematics(Theory,Methods and Applications) 2008年第3期1卷 321-339页

作者： Jürgen Geiser Department of Mathematics Humboldt-Universitt zu BerlinUnter den Linden 6D-10099 BerlinGermany.

This study was suggested by previous work on the simulation of evolution equations with scale-dependent processes,e.g.,wave-propagation or heat-transfer,that are modeled by wave equations or heat ***,we study both parabolic and hyperbolic *** focus on ADI (alternating direction implicit) methods and LOD (locally one-dimensional) methods,which are standard splitting methods of lower order,*** aim is to develop higher-order ADI methods,which are performed by Richardson extrapolation,Crank-Nicolson methods and higher-order LOD methods,based on locally higher-order *** discuss the new theoretical results of the stability and consistency of the ADI *** main idea is to apply a higher- order time discretization and combine it with the ADI *** also discuss the dis- cretization and splitting methods for first-order and second-order evolution equations. The stability analysis is given for the ADI method for first-order time derivatives and for the LOD (locally one-dimensional) methods for second-order time *** higher-order methods are unconditionally *** numerical experiments verify our results.

关键词：偏微分方程算子分裂进化方程 LOD 稳定性分析

Atomic layer deposition to heterostructures for application in gas sensors

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International Journal of Extreme Manufacturing 2023年第2期5卷 171-188页

作者： Hongyin Pan Lihao Zhou Wei Zheng Xianghong Liu Jun Zhang Nicola Pinna College of Physics Qingdao UniversityQingdao 266071People’s Republic of China Institut für Chemie and IRIS Adlershof Humboldt-Universität zu BerlinBrook-Taylor-Str.212489 BerlinGermany

Atomic layer deposition(ALD) is a versatile technique to deposit metals and metal oxide sensing materials at the atomic scale to achieve improved sensor functions. This article reviews metals and metal oxide semiconductor(MOS) heterostructures for gas sensing applications in which at least one of the preparation steps is carried out by ALD. In particular, three types of MOS-based heterostructures synthesized by ALD are discussed, including ALD of metal catalysts on MOS, ALD of metal oxides on MOS and MOS core–shell(C–S) *** gas sensing performances of these heterostructures are carefully analyzed and ***, the further developments required and the challenges faced by ALD for the synthesis of MOS gas sensing materials are discussed.

关键词： atomic layer deposition metal oxides heterostructures gas sensors

A Numerical Investigation for a Model of the Solid-Gas Phase in a Crystal Growth Apparatus

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Communications in Computational Physics 2008年第4期3卷 913-934页

作者： Jurgen Geiser humboldt-universitat zu berlin Department of Mathematics Unter den Linden 6D-10099 BerlinGermany.

We present discretization and solver methods for a model of the solid-gas phase in a crystal growth *** model equations are coupled Eulerian and heat-transfer equations with flux boundary *** a more detailed discussion we consider simpler equations and present time-and space-decomposition methods as solver methods to decouple the multi-physics *** present the error analysis for the discretization and solver *** experiments are performed for the Eulerian and heat-transfer equation using decomposition *** present a real-life application of a crystal growth apparatus,based on underlying stationary heat *** we discuss further error analysis and application to a more complex model of crystal growth.

关键词： Decomposition methods finite-volume discretization error analysis heat equation crystal growth.

IMITATIO ALEXANDRI–THE IMAGE OF DRUSUS MINOR ON BRASS TOKENS OF THE MüNZKABINETT,STAATLICHE MUSEEN zu berlin

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Journal of Ancient Civilizations 2016年第1期31卷 85-122页

作者： Alexa Kuter Munzkabinett Staatliche Museen zu Berlin

Within the group of Roman brass tokens with numerals on the reverse, one type depicting a youthful commander on the obverse stands out. Obviously, it depicts a member of the Julio-Claudian dynasty. The young male is seen from the back, holding a spear. The paper not only discusses this peculiar iconography but also tries to give a new identification: while the commander is usually identified with Tiberius or Germanicus, there are strong reasons to connect the portrait to Drusus minor.

关键词：令牌亚历山大黄铜模仿形象柏林组成部分物质文化

Boosting T cell immunity against cytomegalovirus:a potential strategy combating human aging and age-related diseases

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Signal Transduction and Targeted Therapy 2023年第10期8卷 4417-4418页

作者： Matthias Wirth Walburgis Brenner Oliver H.Kramer Department of Hematology Oncology and Cancer ImmunologyCampus Benjamin FranklinCharite-Universitatsmedizin Berlincorporate member of Freie Universitat Berlin and Humboldt-Universitat zu BerlinBerlinGermany university Medical Center Gottingen Department of GeneralVisceral and Pediatric SurgeryGottingenGermany German Cancer Consortium(DKTK) German Cancer Research Center(DKFZ)HeidelbergGermany Clinic for Obstetrics and Women's Health University Medical CenterJohannes Gutenberg University MainzLangenbeckstr.155131 MainzGermany Department of Toxicology University Medical CenterMainzGermany

In a recent publication in Cell,Hasegawa and colleagues reveal that cytotoxic CD4-positive cytotoxic T lymphocytes(CD4+CTLs)eliminate senescent fibroblasts with a surface expression of the immunologically important human leukocyte antigen class Il(HLA-)and the human cytomegalovirus glycoprotein B(HCMV-gB).1 This implies that a virome-immune cell interaction controls the fate of human skin cells that are linked to the aging process and associated diseases.

关键词： immunity cytomegalovirus cytotoxic

Supported ZnO catalysts for the conversion of alkanes:About the metamorphosis of a heterogeneous catalyst

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Journal of Natural Gas Chemistry 2012年第5期21卷 581-594页

作者： S.Arndt B.Uysal A.Berthold T.Otrebma Y.Aksu M.Driess R.Schomcker Technische universitāt zu berlin Institut fūr ChemieStraβe des 17 Juni 12410623 BerlinGermany Akdeniz university Department of Chemistry07058 AntalyaTurkey Technische universitāt zu berlin Institut fūr Werkstof fwissenschaftenHardenbergstr 4010623 BerlinGermany

ZnO could be a suitable catalyst for the oxidative conversion of CH4,C2H6 and ***,the main drawback is its thermal ***,ZnO supported on ZrO 2,TiO2,γ-Al2O and SiO2 was investigated for the oxidative dehydrogenation of propane and ethane,and the oxidative coupling of *** stability of the supported ZnO is partially improved,but ZnO reacts with the support material,forming new compounds （Zn-zirconates,-titanates,-aluminates and-silicates）,which already occurs below reaction *** might also be the case for many other heterogeneous catalysts.

关键词： oxidative dehydrogenation oxidative coupling of methane oxidative dehydrogenation of ethane oxidative dehydrogenation of propane ZnO